deletions | additions       diff --git a/Payam.tex b/Payam.tex  index 0e02ae6..1e7f131 100644  --- a/Payam.tex  +++ b/Payam.tex 
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\item Same paper, page -- dimensional analysis. Try to do a better job than scaling argument: what are the coefficients? The fact that in the other paper they are off by some distance might be to do with this.  \begin{itemize}  \item I think $t_{\rm h}\sim \ell/c_{\rm s}$ on physical grounds, but Payam says $t_{\rm h}\sim \ell^2\rho/\eta$ from dimensional analysis. Are these compatible? \begin{itemize}  \item Sound speed shouldn't depend on viscosity at all unless we are near supersonic except for near-supersonic  flow. \item \href{http://iopscience.iop.org/0370-1301/66/5/303/pdf/0370-1301_66_5_303.pdf}{Or does it?}  \item \href{http://www.engineeringtoolbox.com/sound-speed-water-d_598.html}{Speed of sound table}, \href{http://resource.npl.co.uk/acoustics/techguides/soundpurewater/content.html#LUBBERS}{$c(T,P)$ fits}.  \end{itemize}